Sale rate per day of week
1) What shortfall are you trying to solve in the current functionality of the addon?
Several items have a higher probability of being sold on specific days. For instance some items tend to sell better right after the weekly maintenance, or some high item level gear sells closer to the weekend for raiding. This would help people not waste AH fees on items that have a low probability of selling on some days.
2) What new functionality do you hope to attain with the addition of this feature?
A new information source would work. Similar to the region sales rate, except allowing for input, such as regionsalerate(2) to reference wednesday's sale rate of the item.
3) How would you or others use this feature?
Adding in this option would allow us to use it in auctioning functions so that we only post items on days that the item has a higher rate of sales chance.